Punch and die devices



Oct. 14, 1969 w. M. HERPICH 3, 7

PUNCH AND DIE DEVICES Filed CCt. 12, 1966 2 Sheets-Sheet l Ila-3 l6 WILLIAM M. HERPICH ORNEYS Oct. 14, 1969 w. M. HERPICH 3,

PUNCH AND DIE DEVICES Filed Oct. 12. 1966 2 SE:-:-ez:-Eli-:-=i i WILLIAM M. HERPICH BY it f) ZLMW J 4 72 phi/Q1? 1 ATTORNEYS United States Patent 3,471,878 PUNCH AND DIE DEVICES William M. Herpich, Litchfield, Conn, assignor to The Torrington Company, Torrington, Conn, a corporation of Maine Filed Oct. 12, 1966, Ser. No. 586,158 Int. Cl. B21k J/46; 1821f /00; 1321i 5/08 US. Cl. -7 10 Claims ABSTRACT OF THE DISCLOSURE There is disclosed a punch member having an elongated body portion and an axial inward recess in a planer transverse end thereof defining an annular ring portion and a centrally positioned protruding planar portion inwardly of said recess, a plurality of ribs each defined in part by side walls and extending radially from said protruding portion to an interior of said ring portion, each said rib also having an end surface which slopes away from said protruding portion toward said ring portion and transversely of the thickness of each rib between its side walls thereby to provide a pressure surface forming area at one side wall of said rib greater than the pressure forming area at the other side wall of said rib.

This invention relates in general to new and useful improvements in punch and die devices, and more particularly to punch and die devices adapted to facilitate the construction of especially configured screw heads and drivers therefore.

Accordingly, it is a primary object of this invention to provide a noval punch and die device adapted to facilitate the production of both screw heads and drivers therefore.

It is another object of this invention to provide a novel punch and die device, adapted for the production of either screw heads or drivers therefor, wherein the device comprises first and second punching stages for performing respectively intermediate and final punching operations.

It is another object of this invention to provide a novel punch member adapted for use in punching screw heads into final form, wherein the punch member includes a recessed end portion having a plurality of radial ribs therein, and wherein axially outermost rib surfaces are especially configured to have a compound angular disposition with respect to a central axis of the punch member.

It is a further object of this invention to provide a novel punch member that is especially configured to define driving surfaces for a screw driving member, wherein the punch member is provided with a plurality of radially outwardly extending channels each having parallel side surfaces and a bottom surface, each bottom surface being of compound angular disposition with respect to a central longitudinal axis of the punch member.

It is a further object of this invention to provide a novel punch member having a recessed end portion and radially outwardly extending ribs, wherein the depth of each of the ribs increases linearly to a greater depth at increased radial distances along each rib from a central axis of the punch member.

It is yet another object of this invention to provide a novel punch member having a plurality of equidistantly spaced radially extending channels, wherein the depth of each of the channels increases linearly at greater radial distances measured along the channel from a central longitudinal axis of the punch member.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings:

In the drawings:

FIGURE 1 is a longitudinal eelvational sectional view, with portions broken away for clarity, of a first stage punch member and a die member of this invention, disposed in co-axial cooperating relation to each other.

FIGURE 2 is an enlarged fragmentary sectional view of portions of the cooperating punch and die members illustrated in FIGURE 1, in their closed condition, and wherein there is illustrated a piece of work material being punch-formed during a first formative stage of a screw head member.

FIGURE 3 is a fragmentary longitudinal elevational sectional view, similar to that of FIGURE 1, but wherein a second stage punch member is illustrated in an operative relation with the die member of this invention, and wherein the configuration of the punch-formed material is illustrated after its initial forming operation.

FIGURE 4 is an enlarged fragmentary sectional view of the punch and die members illustrated in FIGURE 3, in their closed condition, and wherein there is illustrated a screw head being punch-formed into its final configuration.

FIGURE 5 is an enlarged fragmentary sectional view of the punch and die members illustrated in FIGURE 3, following their separation after completing a punchforming operation of the screw head illustrated therein.

FIGURE 6 is an enlarged fragmentary end elevational view of the punch member illustrated in FIGURE 3, taken along the line 66 'of FIGURE 5, and wherein the ribbed formation of the punch member is illustrated in detail.

FIGURE 7 is a fragmentary longitudinal sectional view of another punch and die device of this invention, wherein there is illustrated a first stage punch member in operative relation with the die member of this invention, effecting an initial punch-forming operation for a screw driving member.

FIGURE 8 is a fragmentary elevational sectional view of a second stage punch member in operative relation with the die member of this invention, and wherein there is illustrated a material piece engaged by the die member following the first stage formation, and adapted to be engaged by the final forming punch.

FIGURE 9 is an enlarged fragmentary sectional view of the punch and die members illustrated in FIGURE 8 in an almost-closed position, during the final formative operation of the driving member.

FIGURE 10 is an enlarged fragmentary sectional view of the punch and die members illustrated in FIGURE 9, in their open position, following the final formative stage of the driving member, and wherein the driving member is illustrated partly in section for clarity.

FIGURE 11 is an enlarged fragmentary end elevational view of the finally formative punch member illustrated in FIGURE 10, taken along the line 1111 of FIGURE 10, and wherein the punch channels are illustrated in detail.

Referring to the drawings in detail, reference is first made to FIGURES 1 and 3, wherein there is illustrated a punch and die device 13 comprising a first stage punch member 14, a die member 15, and a second stage punch member 16 adapted for the formation of a screw head.

The first stage punch member 14 includes a punch 17 of generally cylindrical configuration terminating adjacent the die member 15 in a conically chamfered surface 18. The left end of the punch 17, as viewed in FIGURE 1, has a bore 20 therein, which terminates inwardly in the conical surface 21 and communicates with a bore 22 of reduced diameter. The bore 22 terminates adjacent the die member 15 in a flared portion 23 of slightly arcuate configuration. A pin 24 is positioned within the bore 22 of the punch 17, and is adapted for reciprocating movement therein. The pin 24 terminates leftward in a flared head portion 25 from which a plug portion 26 extends outwardly into the bore 20. A compression spring 27 is positioned within the bore about the plug 26, and engages a transverse surface 28 of head portion of the pin 24, for biasing the pin 24 to the right as viewed in FIGURE 1.

The die member 15 includes a die casing 30, and a die insert 31 disposed within a bore 32 of the die casing 38. The die insert 31 has a bore 33 extending throughout the length thereof, in which is positioned a longitudinally movable knock-out pin 34 and a cylindrical piece of rodlike metal material 35, adapted to be Work-formed to have a screw head configuration.

In FIGURE 2 there is fragmentally illustrated the first stage punch member 14 and the die member 15, in a position following that illustrated in FIGURE 1, wherein the punch member 14 is brought into contact with the die member 15, and the end of the work piece 35 that is protruding to the left of the die member 15 has been work-formed against the die surface 23, the bore 22, and the end 29 of the pin 24 to provide the work piece 35 with an annular skirt portion 36. Upon bringing the punch member 14 and die member 15 into contact, the protruding end of the work piece 35 was disposed into contact with the end 29 of the pin 24 of the die member 14, and the movement of the punch and die members together caused the work piece 35 to 'force the pin 24 to the left, thereby compressing the spring 27 until sufiicient spring pressure was realized to effect a sufficient working of the metal of the work piece 35 to fill the void defined by the flared surface 23, and thus create the annular skirt 36 of the work piece 35.

The second stage punch member 16 is of generally cylindrical configuration and includes a punch casing 37 having a bore 38 at one end thereof adapted to receive a punch insert 40 therein, and a bore 41 at an opposite end thereof through which a knock-out pin (no shown) may be inserted in order to remove the punch insert 40 from the casing 37.

The extreme right end of the punch insert 40 as viewed in FIGURE 3 terminates in a transverse surface 42 in which an axially extending recess 43 is provided. The recess 43 is generally cylindrical, and at its radial and axial innermost portion there is provided an axially outwardly extending protuberance 44 which terminates in a transverse planar sulface 45. The outermost limits of the recess 43 comprise an annular generally cylindrical surface 46. A plurality of identical upstanding ribs 47 emanate radially from the protuberance 44 to the annular surface 46 across an innermost portion of the recess 43. The ribs 47 are generally six in number, and are equidistantly circumferentially spaced to define included angles of approximately sixty degrees between adjacent ones of the ribs. Each rib 47 includes parallel side surfaces 48 and 50, and terminates in an axial outermost surface 51, which has a compound slope. The surface 51 of each rib 47 slopes radially outwardly from the central protuberance 44 toward the peripheral edge of the annular surface 46 adjacent the transverse surface 42, and slopes circum-ferentially across each rib 47, between opposite surfaces 48 and thereof.

Upon bringing the second stage punch member 16 into contact against the die member 15, the hardened steel surfaces of the ribs 47 of the insert 40 contact that portion of the work piece 35 which protrudes beyond the die insert 31, and under great pressure forces the softer metal of the work piece 35 to conform to the voids remaining in the recess 43 of the insert 40, thereby forming a screw head 52 from the protruding portion of the work piece 35, having channels 53 therein of an inverse configuration to that of the ribs 47 of the insert 40. Between adjacent ribs 47 are pie-shaped surface portions 49, which are generally linear between the protuberance 44 and the annular surface 46. The depth of the ribs 47, measured along any given radial line from the center of the insert 40 increases linearly as the measurement is taken at greater radial distances along the rib 47 from a central axis of the insert 40, between the surface 49 and the axial outermost rib surface 51.

In FIGURES 7 and 8 there is illustrated another twostage punch and die device 57, comprising a first stage punch member 58, a die member 60, and a second stage punch member 61.

The first stage punch member 58 comprises a punch 62 having large and small diameter bores 63 and 64, at left and right ends thereof as viewed in FIGURE 7. A pin 65 is disposed for sliding movement within the bore 64, the pin 65 having a head portion 66 with a conical surface 67 thereon adapted to mate with conical surface 68 of the punch 62. A rearward surface 70 of the punch portion 66 of the pin 65 is engaged by a compression spring 71 disposed about a longitudinally extending plug 72. The pin 65 also terminates at a right end as viewed in FIGURE 7 in a transverse surface 73. The bore 64 is radially out- Wardly flared at 74, defining between flared surface 74, the end 73 of the pin 65, and the right end of the bore 64 a void 75 for forming a first or preliminary configuration on a work piece 76.

The die member 60 includes a die casing 77 having large and small bores 78 and 80 at left and right ends thereof respectively, as viewed in FIGURE 7. The left bore 78 houses a die insert 81 therein. The insert 81 has large and small bore portions 82 and 83 at left and right ends thereof, and is adapted to receive therein a Work piece 76, having a formative head portion 84 disposed within the bore 82 and a shank portion 85 disposed within and extending through the bore 83.

Upon bringing the punch member 58 into contact with the die member 60, with a work piece 76 therebetween, the head portion 84 of the work piece forces the pin 65 to the left as viewed in FIGURE 7, thereby compressing the spring 71, until a predetermined formative pressure is achieved, at which point the metal of the head portion 84 of the work piece 76 will be forced to fill the void 75, thereby completing the first formative stage and leaving the head portion 84 of the work piece 76 with an annular skirt 87 and an axial protrusion 86. See FIGURE 8.

The die member 60 i then brought into alignment with the second-stage punch member 61. The punch member 61 includes a punch casing 88 and large and small diameter bores 90 and 91 at right and left ends thereof, respectively, as viewed in FIGURE 8. A punch insert 92 is disposed within the bore 90 of the casing 88 in overlying relation to the knockout bore 91.

The insert 92 is generally cylindrical in configuration, and terminates at a right end thereof as viewed in FIG- URE 8 in an annular surface 93 and a plurality of pieshaped protrusions 94. At the radial centermost portion of the insert 92 at the extreme right end thereof there is a depression 95 from which emanate a plurality of channels 96, extending radially outwardly, separating the pieshaped portions 94, and terminating at a peripheral sur- [face 97 of the insert 92. The pie-shaped portions 94 terminate axially in substantially planar surfaces 98.

There are six equidistantly circumferentially spaced channels 96, each of which is defined by parallel side surfaces 169 and 161 and a channel bottom surface 102. The channel bottom surface 102 has a compound slope, being sloped axially throughout the radial extension of the surfaces 102, between the depression 95 and the surface 93. The surface 102 also are sloped circumferentially, across each channel 96, between side surfaces and 101, as will be apparent by reference to FIGURE 10. Thus, the depth of each channel taken along any given radial line from a longitudinal central axis of the insert 92 increases linearly with a greater radial distance from the center line of the insert 92, measured between the surface 98 of each pie-shaped portion and the surface 102 of each channel.

In FIGURE 9 there is illustrated a partially formed driving tool 103, the view being taken during movement of the punch member 61 toward the die member 60, but prior to completion of the movement of these members together. As the members 60 and 61 are moved completely together, the metal of the head portion 84 of the work piece 76 is forced into the cavity defined by the right end of the insert 92 and the bore 90 at the right end of the casing 88.

Upon completion of the punching operation, the punch member 61 is moved to the left as viewed in FIGURE 10, thereby separating the punch member 61 from the die member 60, and leaving a completed screw driving member 103, formed from the work piece 76, having a recess 104 therein, defining driving ribs 105, similar to those of the insert 40 illustrated in FIGURE 3, but having a driving shank 85 for engagement by a power tool or the like.

The punch and die members will generally be constructed of hardened metal, particularly the inserts therefor, in order to withstand the pressure involved in forcing the work piece to conform to the shape of the punch, and yet retain their own shapes during the formative operations.

From the foregoing, it will be seen that novel and advantageous provisions have been made for carrying out the desired end. However, attention is again directed to the fact that additional variations may be made in this invention without departing from the spirit and scope thereof as defined in the appended claims.

I claim:

1. A punch member having an elongated body portion and an axial inward recess in a planar transverse end thereof defining an annular ring portion, a centrally positioned protruding planar portion inwardly of said recess, a plurality of ribs each defined in part by side walls and extending radially from said protruding portion to an interior of said ring portion, each said rib also having an end surface which slopes away from said protruding portion toward said ring portion and transversely of the thickness of each rib between its side walls thereby to provide a pressure surface forming area at one side Wall of said rib greater than the pressure forming area at the other side wall of said rib.

2. The punch member of claim 1 wherein each said rib has parallel side walls and a fiat end surface extending in the direction of the opening out of said recess as an outwardly and endwise sloping planar surface which intersects said central planar portion so that the ribs collectively define therewith a segmentally contoured concave surface within said ring portion, each said outwardly and endwise sloping planar surface also sloping transversely of the respective rib to intersect one of the respective rib side Walls at an acute angle thus to provide said greater and lesser areas at opposite walls of the respective ribs.

3. The punch member of claim 2 wherein segmental voids a-re defined between adjacent ribs having depths measured axially from said outermost surfaces and being of greater depth at distances thereof measured radially outermost from said first portion.

4. The punch member of claim 3 wherein said depth increases substantially linearly with radial distance measured along said ribs firom said first portion.

5. The punch member of claim 1 wherein said punch member comprises a punch insert in combination with a punch casing for cooperation with a die insert in combination with a die casing.

6. A punch member having a cylindrical punch end thereon; said end being shaped to define a plurality of eqpidistantly circumferentially spaced channels extending radially outwardly from a center of said punch end; each of said channels including parallel first and second wall portions of difierent depths on opposite sides of a corresponding channel base surface.

7. The punch member of claim 6 wherein the depth of each of said channels increases from a depth at a radial centermost portion and slopes to a maximum depth at its radial outermost portion.

8. The punch member of claim 7 wherein each channel base surface slopes circumferentially to be of greater depth adjacent one wall portion than an associated other Wall portion thus to provide said opposing different depth wall portions.

9. The punch member of claim 8 wherein each associated pair of said channel wall portions are parallel and the channels are spaced substantially sixty degrees apart, terminating radially inwardly in a recessed portion.

10. The punch member of claim 6 wherein said punch member comprises a punch insert in combination with a punch casing for cooperation with a die insert in combination with a die casing.

References Cited UNITED STATES PATENTS 3,176,329 4/1965 Frame 1027 2,015,878 10/1935 Trotter -45 2,151,776 3/1939 Koesteir 10l0 2,180,633 11/1939 Holt 8545 2,238,960 4/1941 Wilcox 10-l0 2,716,759 9/1955 Merlin et a1. 1026 2,939,160 6/1960 Mitchell 10-26 3,166,769 1/1965 Wieber 1026 3,324,491 6/1967 Gutshall 10-26 FOREIGN PATENTS 1,232,468 10/1960 France.

CHARLES W. LANHAM, Primary Examiner E. M. COMBS, Assistant Examiner 

